mirrors/django
mirrors/django
0
0
Fork 0
mirror of https://github.com/django/django.git synced 2024-11-29 14:46:18 +01:00
Code Issues Releases Wiki Activity

Fixed #30494 -- Disabled __year lookup optimization for indirect values.

Browse Source 
The previous heuristics were naively enabling the BETWEEN optimization on
successful cast of the first rhs SQL params to an integer while it was
not appropriate for a lot of database resolved expressions.

Thanks Alexey Chernov for the report.
This commit is contained in:
Simon Charette 2019-05-20 18:53:13 -04:00 committed by Mariusz Felisiak
parent 1d0bab0bfd
commit 4d1420947e
2 changed files with 20 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

25
django/db/models/lookups.py
View File

@ -508,21 +508,16 @@ class YearExact(YearLookup, Exact):
lookup_name = 'exact'
def as_sql(self, compiler, connection):
# We will need to skip the extract part and instead go
# directly with the originating field, that is self.lhs.lhs.
lhs_sql, params = self.process_lhs(compiler, connection, self.lhs.lhs)
rhs_sql, rhs_params = self.process_rhs(compiler, connection)
try:
# Check that rhs_params[0] exists (IndexError),
# it isn't None (TypeError), and is a number (ValueError)
int(rhs_params[0])
except (IndexError, TypeError, ValueError):
# Can't determine the bounds before executing the query, so skip
# optimizations by falling back to a standard exact comparison.
return super().as_sql(compiler, connection)
bounds = self.year_lookup_bounds(connection, rhs_params[0])
params.extend(bounds)
return '%s BETWEEN %%s AND %%s' % lhs_sql, params
# Avoid the extract operation if the rhs is a direct value to allow
# indexes to be used.
if self.rhs_is_direct_value():
# Skip the extract part by directly using the originating field,
# that is self.lhs.lhs.
lhs_sql, params = self.process_lhs(compiler, connection, self.lhs.lhs)
bounds = self.year_lookup_bounds(connection, self.rhs)
params.extend(bounds)
return '%s BETWEEN %%s AND %%s' % lhs_sql, params
return super().as_sql(compiler, connection)
class YearGt(YearComparisonLookup):

11
tests/db_functions/datetime/test_extract_trunc.py
View File

@ -4,7 +4,8 @@ import pytz
from django.conf import settings
from django.db.models import (
DateField, DateTimeField, IntegerField, Max, OuterRef, Subquery, TimeField,
DateField, DateTimeField, F, IntegerField, Max, OuterRef, Subquery,
TimeField,
)
from django.db.models.functions import (
Extract, ExtractDay, ExtractHour, ExtractIsoYear, ExtractMinute,
@ -108,6 +109,14 @@ class DateFunctionTests(TestCase):
query_string = str(qs.query).lower()
self.assertEqual(query_string.count(' between '), 1)
self.assertEqual(query_string.count('extract'), 0)
# an expression rhs cannot use the between optimization.
qs = DTModel.objects.annotate(
start_year=ExtractYear('start_datetime'),
).filter(end_datetime__year=F('start_year') + 1)
self.assertEqual(qs.count(), 1)
query_string = str(qs.query).lower()
self.assertEqual(query_string.count(' between '), 0)
self.assertEqual(query_string.count('extract'), 3)
def test_extract_year_greaterthan_lookup(self):
start_datetime = datetime(2015, 6, 15, 14, 10)